Refrigerated display cases are widely employed for effectively merchandising food products while maintaining such in prime condition. Yet, because of the significant energy usage requirements of such cases, particulary open front display cases, there is a tendency to cut back on usage thereof in recent times. Energy is required for refrigeration of these cases, for antisweat heat during refrigeration, and often for defrosting. Creative concepts have been put forth recently for decreasing energy consumption of refrigerated display cases. In U.S. Pat. No. 4,026,121, a special reverse flow air defrost system is taught. In patent application Ser. No. 810,973, a unique cover arrangement is taught in combination with reverse flow air defrost. Both developments result in significantly less energy usage. Also basically disclosed in said application Ser. No. 810,973 is an optional feature of diversionary use of electrical power normally employed for antisweat heat through a special control for defrost heat during the defrost mode of the display.